Speedometer drive-gear.



1. K. STEWART.

' SPEEDOMETER DRIVE GEAR.

APPLICATIONFILVEZD JUNE H, 1913.

Patented July 27, 1915.

. STATES PA;

' LBYEIST AVAILABLE cos @FFICE.

JOHN K. srnwnnr, or CHICAGO, IIJLrNoIs, Ass'I'sNon 'ro srEw-An'r-wanunn sensuoun'rnn oonrom'rIou, or CHICAGO, ILLINOIS, A conroner'rou or VIRGINIA.

SPEEDOMETE'H, IKRIVE-GEAR.-

. Specification of Letters Patent.

Patented July 27, 1915.

Applicationfiled June11, 1913. Serial No. 773,016.

To all whom it may concern:

' Be it known that 1, JOHN K. STEWART, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful. Improvements in Speedometer Drive-Gears,

- of which the following is a specification,

- view of on automobile chassis showing the tion of ordinary spur gears were erngloyed for connecting the propeller shaft,

drive gear installed thereon. Fig. 2 is a detail view partly in section, such section being taken axially with respect to the propeller shoft of the vehicle. Fig. 8 is a partly sectional view of the device, section being taken as indicated at line 3-3 on Fig. 4. Fig. 4. is an end elevation of the housing for the gears. I

As indicated in Fig. 1 the present device is designed to be installed so as to transmit to the speedometer, A, the rotation of that part of the propeller shaft, B, which connects the change speed goon-C, with. the rear ,exle and the roedwheclsnl), driven thereby, since in this way the rotational speed which is being measured by the speedometer will always bear-a fixed. relation to the actual speed of rotation of the road wheels, I).

It will he seen that if a. simple comhinaand the flexible shaft, E, of the speedometer, the

said flexible shaft would haves directly'for wurd'trend and would thus conflict with the change eerhox, (3; For this reason the two sh. ts are connected by spiral goers so thatithe flexible shaft, E, is given: a. forwardiy oblique trend, whereby it easil passes to one side of the gear box, 0, an

thence forward end up'wwrd tothe speedometer, A, mounted on the dash-hoard. i.

Fig. 2 shows the driving gear, 1, which is secured fast to the propeller shaft, B, and is provided with a hub sufiiciently extended to present journal surfaces, 1, to the hearing rings, 2,. carried at either end of the housing, 3. This spiral driving gear, 1,

meshes with a spiral driven gear, 4, jour-' naled 1n the upper portion, 3, of the housing,3, and connected with the flexible shaft, E, through a pair of spur gears, 5 and 6, respectivel These spur gears, 5 and6, are employed for speed-changing purposes in order to avoid too great a. difference in the relative 51.19 oi the driving and driven gears, 1 and 4, thus keeping the size of the device within convenient limits.

It will be noted that the housing, 3, comprises a casting and three cover plates, two

of which, 3", 3 constitute end walls forthe notion of the housing encircling the propeller shaft, 13, and the third, 3, serving to close the portion of the housing in which the spur gears, 5 and 6, are contained. This I,

cover plate, 3, is further provided with a.

journal bearing, 3, for the stud shaft, 6,

of the final gear, 6, to which'shaftthe flexible shaft, E, may be coupled in the usual well known manner. In assembling the device it may he noted that the gear, 4:, will he introduced into its portion of the housing fromthe lower portion of the housing, 3,

before the end plates, 3 are applied, and whcrrit is, properly positioned in the upper portion of the housing at 3*, i short shaft, 4, is forced into said gear, i, and the end hearing plug, 3, is inserted in the housing,

3. The spur gears, 5 and 6, will he positioned before the cover, 3, is applied, the shsft, 5",heing interlocked with the shaft, t, as indicated in Fig, 3. With the end letes, 3, and the bearing rings, 2, removed It will be seen that the housin can he slipped on to the propeller shaft for meshing the spiral gears,and thefrings, 2, and the plates, 3", may he subsequently applied to definitely position the device, packing rings, 7 be ng inserted etthe some time to remix; t e lubricant with should be packed.

power shaft, a

which" the housing gear rigid therewitlno tramof'gearsudoph ed to be driven by suidgeunand a housing for said train, comprising a portion whose.

boreis greater than the diameter of the gear on theshaft; bushings adapted to-be two inter-communicating chambers; and an opening in the first chamber; a gear dimensioned to be inserted through said opening and said chamber into the second chamber;

a shaft for said gear; a journal bearing for said shaft formed at one side of the second chamber, the other side having an aperture and a recessed plug dimensioned to fit in said aperture for journaling one end of the gear shaft.

3. A gear housing comprising two chambers connected by a bore adapted to serve DEST AVAILABLE COP' as a journal bearing for a shaft, theside 20 wall of one of said chambers being removable to admit gears to said chamber, and having an extension bored to serve as a journal bearing for a second shaft, the other chamber having a I circumferential opening, adapted to admit a gear to said chamber, and having a lateral opening axially located to admit the shaftifor said gear, and a recessed plug adap'iiitiifto fit said aperture to serve as a journal fieiiring for such shaft.

In testimony whereof I have hereunto set"- my hand at Chicago,"Illinois, this 6 day of June 1913.

JOHN K. STEWART.

Witnesses:

C. B. SMITH, S. Henson. 

